Improvement in working sheet metal



ll'wrrnn Sterns Paritair @tirreno S. B. MILLER AXD E. \V. \VHlTEHEAD, OFNEW'ARK, NETV JERSEY.

IMPROVEMENT IN WORKING SHEET METAL.

- Specification forming part of Letters Patent No. ll/-s lated May 1li,1-"i(.

To @ZZ 'whom t may concern:

Be it known that we, SYLvns'rnR B. MILLER and Eznx W. VHITEHEAD, ofthecity ot' Newark, county of Essex, and State of New t Jersey, haveinvented a new and useful improvement in machines for forming concentricsurfaces in metals, such as dishes, lamp `and eandlestick bottoms, andother analogous shapes; and we do hereby declare that the following is afull, clear, and exact descriptionot' the construction and operation ofthe same.

The nature of our improvement consists in substituting pressure androtation to one of the dies, instead ot' a drop and percussion force, asheretofore used, for forming and stretching the material. It is to beunderstood that the improvement relates to making forms that areconcentric to the axis ot' rolalion ofthe die. The drop and percussionprocess makes it necessary to have a firm and solid bed to resist theblows, involving material expense in the machinery, and is likely todamage the work if it is deep and the material lacking in ductility,often requiring a number of successive dies and blows, consuming timeand power to a great extent, whether the drop-screw or lever press isused l'or the purpose. As percussion acts by im pulse or reeiprocation,it is not so easily graduated in its action for stretching the niaterialto be formed as by rotation and gradual pressure. The rotation of thedie aids the pressure in stretching the material gradually to meet thedepth of the die by using a less number of dies than in the old plans.Percussion or pressure alone will tear or otherwise fracture the metalif the blow extends beyond its stretch or ductility before it comes incont-act with the under die; hence a graduated succession of dies isrequired, each one being within the limit of the duetility of the metal.As rotary motion and pressure actgradually and not suddenly, as inpercussion, a less number of dies will answer in our improved plan thanin the old plans, besides admitting of using a material in ferior inductility to what is required in the drop and other presses, allowingthe use of any number of, dies in one machine that may be desirable toact at the same time, the whole being arranged with less difficult-y andexpense than can be done by the drop and other presses, and the l 1power, and of a better quality.

work executed with greater rapidity, with less As the male die performsmost of the stretching, a mere ring will answer for the female die insome kinds of work in our improved'plan to sustain the material operatedupon, as the pressure is gradual. The ring supporting the material atthe outer edge ofthe depression holds it up, and a shoulder on the outeredge of the male die comes in contact with the metal rest ing upon thefemale die and stops its descent, truing the edge around the depression,and making less expense for the female die than is required in the dropplan, as in the latter case a perfect lit between the whole surfacesmust be made between the two dies. In the drop press, this shoulder, infalling upon the material, tends to thin the metal at this part, andpnless guarded by this shoulder would destroy the metal by making apuncture; whereas, in the improved plan. the depression being gradual,no such effect is produced. This thinning of the metal exterior to thedepression is objectionable in work requiring a true face. This is anadditional modification of the dies, costing less than full or solidsets.

The annexed drawings make a part of this specification, in which Figurel is a side elevation ofthe entire machine, showing the die raised upready to receive the material. Fig. 2 is a sectional elevation throughthe middle from front to rear. Fig. 3 is a front View from right toleft. Fig. i is the male die and spindle, separate from the machine.Fig. 5 is the depressing or countersinking face of the male die, with apunch or drill attached for making an aperture in the depression whenneeded. Fig. Gis the depressed or countersinking face of the female die,with a hole in the center to match the drill or punch in the male die,thus making the depression and puncture at one operation. Fig. 7 is thedepressing or countersinking face of the male die without a drillattachment. Fig. 8 is the depressed or countersunk face of the femaledie without any aperture,these dies being designed for work with fullfaces. Countersinking iu the sense here used is not cutting ont andremoving the material, but is depressing it to a definite shape.

Like letters refer to like parts throughout the drawings.

AA is the base of the machine 5 .B B, the female die resting upon it.The countersink depression in this case is a section ol' a sphere for apattern. Other patterns admitting of the rotation of one oi' the diescan be used.r

C is the standard'for sustaining the male die and its spindle. Othermeans may be adopted for holding the spindle and die, as in some casesgreater space may be needed between them and the standard.

D D are the guides for attaching the spindle to the standard, and toallow of free rota tion and ease of up-and-down motion.

E E are the bearings of the spindle guiding the male die to a propercontact with the female die.

F is the bearing or swivel journal l'or raising and depressing thespindle7 and still allowl it to rot-ate.

G is the swivel which embraces the spindle at F.

H H are the collars ot' the swiveljournal F.

I is the lever for working the spindle up and down. This swivel embracesthe spindle7 allowing it to rotate freely, bearing against the collarsin lifting it up and down, and is placed in a suitable opening in thelever, and is attached to it by suitable arms or projections I,projecting through the oblong holes in the sides ofthe opening in thelever. y

J is the fnlcrnm ofthe lever, and K the end of it. i

L is a spiral spring for raising the spindle through the lever, it beingpulled down by hand in this case. Then desired, it can be madeself-acting.

H is a pulley to work the spindle by a belt.

N is the depression or `form of the face ol" the female die.

O is the punching or drillinghole in Fig. G.

l? is the drill in Figs. et andi. The drill and hole must be so made asto not obstruct the working of the dies, and at the same time make asmooth hole,

Q Q is the face of the male die.

lt R are ridges raised upon the face of the male die and rounded ontheir edges, so as to not cut or otherwise injure the material. Theseridges may be made narrow or wide, curved, or straight from thecenterout. The Wide faceridges are less likely to abrade or disgnre thematerial. ln some cases it may be necessary to use the face smooth,owing to the delicacy ofthe work. The ridges are preferable whereadmissible, as they produce the effect with less pressure, operatingupon less surface at a time, causing it to stretch easier, as well assink under the pressure and rot-ation ofthe di e.

The iirst cost of construction, as well as in working our improved plan,is less than in the old plans.

XVe do not claim a rotating die or countersink for making depressions bycutting and removing the material` as the means for doing so are wellknown, and are 'for another purpose.

le claim- The employment of the die E, when constructed as described andused in connection with the lower die, N, for extending or stretchingthin metal plate by pressure and rotary motion combined.

SYLVESTER B. MILLER. EZRA V. -WTHITEHEAD.

lfitiiesses:

.ToirN H. Thus, TnnoDoRn M. TiMs.

